Jessica Chastain and Sebastian Stan recently starred together female spy thriller The 355. It’s the latest film by Simon Kinberg (the very same person who wrote Mr. & Mrs. Smith, which brought together Brad Pitt and Angelina Jolie) where the actors play fellow spies who face off at the end (spoiler alert).Throughout the film, there’s a lot of sexual tension and playful banter between the two. Not to mention, there are some great action sequences too (one of which landed Chastain in the hospital).RELATED: Forget Leonardo DiCaprio: Jessica Chastain Truly Is Unrecognizable As Tammy Faye BakkerAnd while the reviews for the film may be lukewarm despite a cast that also includes Lupita Nyong'o, Diane Kruger, Bingbing Fan, and Penélope Cruz, it’s worth checking out for Chastain and Stan’s scenes alone.Clearly, the two actors have chemistry (some have even compared it to Chastain’s onscreen pairing with longtime pal Oscar Isaac). And while they have an incredible onscreen relationship, (though not to the point where fans feel bad for Jessica's real-life husband), one can’t help but wonder how close the two actors truly are in real life.

The Co-Stars Had Worked Together Previously

Perhaps, some fans don’t realize that Stan and Chastain had already starred in a film together several years back. It was the 2015 sci-fi drama The Martian, which is headlined by Matt Damon, Chastain, and Kristen Wiig (meanwhile, Kinberg served as a producer).

The movie is an ensemble piece (the cast includes Kate Mara, Sean Bean, Jeff Daniels, and Benedict Wong) and so, Stan and Chastain didn’t really have a lot of scenes together.

Nonetheless, Stan later revealed that Chastain was one of the reasons he agreed to do the movie.

“It is about commitment, and that’s why it works with this group. They’re so versatile and not afraid to take chances,” the actor remarked during an interview with Tim Lammers’ Tim Talks.

“Jessica Chastain, Michael Pena — everybody — they elevate you when they’re around you. It makes you realize, ‘I’m a better actor because of these guys.'” While speaking with FilmInk later on, Stan recalled, “I had a great experience working with Jessica…”

Jessica Chastain Was Responsible For Bringing Sebastian Stan Into ‘The 355’

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The idea for The 355 essentially came together after Chastain attended the Cannes Film Festival in 2017 (where she served on the jury). Looking around at the posters, she noticed that all the upcoming action films were just headlined by men.

That’s when she decided she wanted to make an action film led by women. “Sometimes you have to have an idea and follow through with it,” Chastain told The Knockturnal.

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Knowing what she wanted to do, Chastain got in touch with Kinberg, tapping him to direct the movie. For the longtime filmmaker, the opportunity to reunite with the actress sounded too good to pass up (aside from The Martian, Chastain also joined Kinberg’s X-Men: Dark Phoenix previously).

“I think we were having dinner and she said, ‘Look, I have this idea of doing a female ensemble spy movie,’” Kinberg recalled while speaking with The Wrap. “And I got really excited by every element, which is, I got excited about working with Jessica again, because I adore her and think she’s one of the greatest living actors we have…”

It’s the first spy film Kinberg has worked on since Mr. & Mrs. Smith.

Meanwhile, when it came to putting the cast together, it seems that Chastain already had certain actors in mind. For starters, she contacted Stan whom she had stayed in touch with since The Martian. “We stayed friends after that, and she reached out about the script for The 355 and asked if I would consider playing the part of Nick,” the actor recalled.

“I was so taken with that offer that I immediately said yes to the opportunity to work with her again.” Stan said that doing the film was a “no-brainer.”

“The film’s script was great,” he remarked. “It was fun, entertaining, unpredictable, original and had great action, character development and plot twists.”

Jessica Chastain And Sebastian Stan Developed Their Characters’ Romantic Arc Together

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In the film, Chastain’s Mace and Stan’s Nick relationship remain undefined for the most part. But it’s clear there’s something going on between them. That’s exactly what the actors had in mind for this storyline in the film. And as it turns out, it was something that Chastain and Stan worked on developing together.

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“There was more unexplored territory there between them,” Stan explained. “And that was only slightly suggested in the script and then when we started to work on it, we developed that much more, and I feel like really great scenes came out of that.”

The actor also said that the relationship they presented onscreen was “something that came out of the conversations between Simon, Jessica and I.”

At the moment, it doesn’t seem like Chastain and Stan would be collaborating again anytime soon. Both have films coming up but not with each other. Since Chastain has been producing more and more though, it’s probably just a matter of time before she calls Stan again. Interestingly, Chastain is producing a new film that Kinberg is set to direct.

It’s the drama thriller Wayland, which is said to be another ensemble film. Currently, there are also no plans for a sequel to The 355 with Chastain telling the National Post, “The reality is, I didn’t make this to be an action star.”

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